This invention relates to a tool to perform mechanical operations in hard-to-reach locations. In particular, it relates to a tool to install and remove hose clamps in the crowded engine compartment of a modern automobile.
The engine compartment of a typical automobile has become increasingly crowded in recent years, partly as a result of the reduction in size of the whole car and partly because of the many new devices being packed into the engine compartment. As a result, both those assembling the car and those working on it to maintain it in good condition or to repair it have great difficulty in reaching some of the parts. Radiator and heater hoses are among the parts that are particularly difficult to reach. In addition to being accessible only with great difficulty, each end of each of these hoses is clamped onto a nipple on the radiator, heater, or engine by a resilient circular clamp that squeezes the end part of the hose tightly and binds it watertight to its nipple. The clamp can be loosened only by exerting considerable pressure in the proper direction on lugs extending outwardly from each end of the circular main part. This pressure on the lugs to move them toward each other expands the diameter of the circular main and must be done either to install a new hose on a nipple or to remove a hose that must be replaced. In some instances, a clamp is installed so that its lugs are not in position to allow the necessary pressure to be exerted on them to loosen the clamp when it is necessary to remove it, and for this and other reasons, it is sometimes necessary that large components of the car be removed or loosened to make it possible to reach a particular hose clamp.
Workers on an assembly line have the advantage of having powered tools with which to manipulate a hose clamp to install it on a hose and the hose on a nipple as a car is being built, and they have the additional advantage that the order of assembly of parts can be arranged to allow the hose clamps to be installed when there is as much access as possible to the locations where those clamps must be fitted. However, the power tools sometimes apply too much power in squeezing a clamp and stress it beyond its elastic limit. In addition, even when the order of assembly is chosen carefully, it is not always possible to provide the amount of room necessary for a power-assisted tool.
Efforts have been made in the past to provide tools to manipulate circular, resilient hose clamps. U.S. Pat. Nos. 2,677,982, Arras et al., and 3,161,086, Kircher, show tools in the form of pliers to grip a clamp formed of spring rod having a round cross section bent into an arc of greater than 360.degree. and provided with ends that extend approximately perpendicularly to the arcuate part. The arms of the pliers extend much father apart than would be permissible in the cramped engine compartment of modern car, and it would be necessary for a person using the pliers to reach into the immediate vicinity of the clamp location, something that is frequently physically impossible in today's cars. Moreover, pliers are normally held so that their pivot pin is between the user's hand and the hose clamp, which is not ergonomically correct for the installation of hose clamps in crowded engine compartments.
Pasqualone et al. show a tool that uses a threaded rod to transmit pressure to the ends of a clamp. While the cross-section of the tool at the end that grips the clamp is of minimal size, the threaded rod would take a long time to operate to install or remove each clamp. One of the requirements of mass production of automobiles is that every operation be carried out in as short a time as is possible. Even in the case of replacement of a hose and hose clamp in a repair station, where hose clamps are not put on nearly as often as on an assembly line, time is important, and operation of the threaded mechanism of Pasqualone et al. would take too long.
Reeves shows a wrench U.S. Pat. No. 1.029,142 in which a first member encircles a second, straight member to be guided by the latter to slide along it to force two jaws, one on each of the two members, toward each other in response to pivotal movement of a handle pivoted on the second member. The handle is connected to the sliding part by two links, and, as in the case of the pliers of Kircher and Arras et al., is pivoted at a location between the jaws and the user's hands.
Similarly, U.S. Pat. No. 1,051,727 to Gardner shows a wrench that has two handles, one of which is pivotally supported on the other at a location between the jaws and the part of the latter handle held by a user.